CHANGES IN BLOOD-LEVELS OF PROTEINASE-INHIBITORS, PREGNANCY ZONE PROTEIN, STEROID CARRIERS AND COMPLEMENT FACTORS INDUCED BY ORAL-CONTRACEPTIVES

Three low-dose oral contraceptives Trinordiol (R), Gynatrol (R), and M arvelon (R), containing ethinylestradiol (EE) in combination with trip hasic levonorgestrel (LNg), monophasic levonorgestrel, and monophasic desogestrel (DSG), respectively, were given to 65 healthy women, n=21- 22 in each group. Blood levels of antithrombin III (AT III), (alpha(2) - macroglobulin (alpha(2)M) alpha l-antitrypsin (alpha(1)at), compleme nt factors (factor B, C3, C4), pregnancy zone protein (PZP), corticost eroid binding globulin (CBG), sex hormone binding globulin (SHBG) and albumin were measured before treatment and during the first and third treatment cycles. AT III levels decreased and alpha(1)at levels increa sed in all three groups during treatment. Alpha(2)M increased during c ycle 3 in the Trinordiol and Gynatrol groups. CBG, PZP and SHBG levels increased in all 3 groups, the CBG and PZP increase being higher in t he Marvelon group than in the Gynatrol group. Increases in SHBG levels were found in the order Marvelon > Trinordiol > Gynatrol. Plasma leve ls of complement factors B, C3 and C4 remained unchanged. It is conclu ded that the increase in alpha 1at partly compensates for the fall in AT III, that the rise in PZP presumably enhances fibrinolysis, and tha t LNg has higher anti-estrogenicity and androgenicity than DSG.